Device for editing and outputting information for a motor vehicle driver

ABSTRACT

A device for editing and outputting information for a motor vehicle driver, comprising a receiver for digitally coded traffic messages and an auto navigator, which is designed to determine the instantaneous position of the vehicle and to calculate route recommendations, linked by a data transmission device.

FIELD OF THE INVENTION

The present invention relates to a device for editing and outputtinginformation for a motor vehicle driver.

BACKGROUND OF THE INVENTION

The Radio Data System (RDS) enables digital data to be additionally andinaudibly transmitted in parallel with radio programs, in a datachannel. Specifications of the Radio Data System for VHF sound radio aredefined, inter alia, in the publication Tech. 3244 -E, March 1984 of theEuropean Broadcasting Union (EBU). Besides receiving radio signals,radio receivers having the requisite RDS decoders can receive and decodetransmitted data, using the same receiving part. The data transmissiontakes place in 32 groups of 108 bits each, a specific service beingassigned to each group. The group 8a is provided for transmittingdigitally coded traffic messages.

The structure and coding of these traffic messages are defined in detailin the proposed standard, ALERT C, November 1990, published by RDS ATTALERT Consortium. The essential elements of a traffic message are thelocation of the occurrence and the event. This information is cataloged,i.e., a unique code is assigned to each location and event that haverelevance to traffic. The locations are integrated in the location tablealong existing streets to reproduce the pattern. In addition to thecustomary receiver devices having an RDS decoder, in order to utilizethe traffic report channel TMC (Traffic Message Channel), devices areneeded for decoding, storing, further processing, and outputting thetraffic messages.

Auto navigators have also become known, which determine theinstantaneous position of a vehicle and, with the aid of a digitallystored road map and an entered travel destination, calculate and displayproposed routes. To determine position, sensors, which detect the motionof the vehicle on the road surface, as well as satellite positioningsystems (GPS) can be used. The calculated routes proposals can be outputas maps with the proposed routes marked, or as an instruction on how toproceed at intersections and turn-offs. Thus, auto navigators are known,for example, where an arrow symbol that assumes different shapes anddirections shows the motor vehicle driver the way. However, in knownauto navigators, the route recommendations and, in some instances, otherinformation are determined merely on the basis of a digitally storedroad map, without giving consideration to vicissitudes in the roadnetwork, such as temporary irregularities resulting from traffic jams orstoppages.

SUMMARY OF THE INVENTION

The object of the present invention is to improve the information givento the motor vehicle driver over known devices and systems in the eventof obstructed traffic.

This objective is achieved in accordance with the present invention inthat a receiver for digitally coded traffic messages and an autonavigator, which is designed to determine the instantaneous position ofthe vehicle and to calculate route recommendations, are linked by a datatransmission device.

The device according to the invention has the present advantage thatdigitally coded traffic messages are taken into consideration whenproposed routes are calculated and displayed. Moreover, the deviceaccording to the present invention plays a role in not giving thevehicle driver an unnecessary excess of visual or acoustic trafficmessages that are not relevant to his or her probable route.

The device according to the present invention can be so conceived that awholly autonomous receiver for digitally coded traffic messages and awholly autonomous auto navigator are linked, for example, via a databus. However, it is also possible that the receiver or parts of thereceiver used for managing, decoding and outputting traffic messages,together with essential components of the auto navigator, are realizedby different programs in a processor, the data being transmitted alongthe lines of the present invention by accessing a shared memory.

To enable the auto navigator to respond as quickly as possible totraffic messages, one preferred specific embodiment of the presentinvention provides for new traffic messages received by the receiver tobe transmitted spontaneously to the auto navigator.

In certain operating states, however, when the entered destination ischanged or when the auto navigator is switched on, it can beadvantageous, however, for the traffic messages to be transmitted inresponse to a request by the auto navigator.

An important procedure in a receiver for digitally coded trafficmessages--also referred to in the following as TMC system--is selectingreceived traffic messages in accordance with predefined criteria. On theone hand, this is important for the vehicle driver in that he is notdistracted by a multiplicity of traffic messages, which are of noimportance to him, from those traffic messages which relate to hisprobable route. On the other hand, it is necessary to select the trafficmessages to be transmitted to the auto navigator to avoid overloadingthe computer in the auto navigator. Therefore, a further embodiment ofthe device according present invention provides for the auto navigatorto calculate criteria for selecting traffic messages to be transmittedto the auto navigator from the instantaneous position and from anentered destination and to transmit them to the receiver.

While a decidedly well-directed selection can be made automatically andlikewise through manual input with the aid of the auto navigator, anautomatic selection can be made with the aid of the TMC system on thebasis of the instantaneous position in that traffic messages areselected, for example, which relate to locations having a predefineddistance from the instantaneous position. For this, one furtherembodiment of the device according to the present invention provides forthe auto navigator to transmit the instantaneous position to thereceiver and for the receiver to select traffic messages on the basis ofthe transmitted position.

In this case, the instantaneous position can be transmitted from theauto navigator to the receiver after a predefined distance has beencovered or a predefined time period has elapsed, or in response to apolling by the receiver.

The effect that the events communicated by the traffic messages have onthe calculation of the route recommendations can vary greatly from eventto event. In order not to burden the auto navigator in its computationalwork with the evaluation of irrelevant events, another furtherembodiment of the present invention provides, in addition, for anevent-oriented selection criterion to be transmitted by the autonavigator to the receiver.

Due to the fact that selection criteria are produced and because theycan be entered at the receiver, several variants exist with respect toselecting the traffic messages to be output. One specific embodiment ofthe present invention provides for selecting the traffic messages to beoutput in accordance with a criterion that is entered independently ofthe auto navigator.

The effect that this measure has on the outputting of traffic messagesis that traffic messages, which do not lie on the route proposed at anyone time by the auto navigator, are also output. However, trafficmessages, which lie on the proposed route, are not output. If thecontents of such traffic messages do not require leaving the proposedroute, the auto navigator does not indicate an alternative route. Thusthe vehicle driver will travel on that proposed route for which atraffic message is at hand, but has not been output.

To enable traffic messages output to the vehicle driver to be adapted tothe momentary route recommendation, another specific embodiment of thepresent invention provides for a criterion for selecting trafficmessages that are to be output to be transmitted by the auto navigatorto the receiver. In this case, the number of traffic messages to beoutput can be limited, in particular, in that the criterion selectsthose traffic messages which relate to the route in question when noother route can be recommended by the auto navigator. Here, however, anypossible interest the vehicle driver might have in traffic messagespertaining to other routes is ignored.

To meet the vehicle driver's need for information that goes beyond that,a third specific embodiment of the present invention provides fortraffic messages to be output both in accordance with an enteredcriterion as well as in accordance with a criterion transmitted from theauto navigator to the receiver.

To accommodate the vehicle driver's momentary need for information, thevehicle driver can also be provided with the capability to choosewhether the traffic messages will be selected in accordance with acriterion that he or she selects and/or in accordance with the criterioncalculated by the auto navigator.

One advantageous embodiment of the device according to the presentinvention provides for the auto navigator to calculate routerecommendations in consideration of the traffic messages. In such acase, traffic messages which pertain to traffic jams or slow movingtraffic can be converted into traffic resistance values, which are thencompared to determine various alternative routes.

The device according to the present invention preferably provides forthe auto navigator to be able to decode traffic messages.

To decode the digitally coded traffic messages, location and event listsare necessary which conform with those which were used in thetransmitter-end coding. Therefore, one advantageous refinement of thisfurther embodiment provides for the auto navigator to possess adigitally stored road map, which, in addition to the data required fornavigational purposes, also includes a location-code list provided fordecoding the traffic messages.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a block diagram of a device according to the presentinvention;

FIG. 2 shows a detailed representation of the device according to FIG.1;

FIG. 3 shows a flow chart for the initialization process after thedevice according to the present invention is switched on;

FIG. 4 shows a flow chart for elucidating the receiving and the routingof traffic messages to the auto navigator;

FIG. 5 shows a flow chart for elucidating the transmission of trafficmessages to the auto navigator when working with a new position or whenworking with a new selection criterion; and

FIG. 6 shows a flow chart for the dynamic route recommendation by meansof the auto navigator.

The same parts in the various Figures are provided with the samereference numerals.

DETAILED DESCRIPTION

In the case of the device according to FIG. 1, a radio receiver 1 isequipped with a device (not shown in detail) for decoding RDS signalsand with a device for decoding and for managing traffic messagescontained in the RDS signals. The device is referred to in the followingas TMC system. To the extent that the transmissions received via anantenna 2 contain RDS signals with digital traffic messages (trafficmessage=TM), these signals are decoded and output via a loudspeaker 3with the aid of voice synthesis. Besides the operation of the radioreceiver, an operating control unit 4 enables the operation of the TMCsystem, for example, in order to select incoming messages in accordancewith predefined criteria or to have already previously output messagesoutput again.

The TMC system in radio receiver 1 is linked via a data bus 5 to an autonavigator 6. Connected to auto navigator 6 are a display device 7, anoperating control unit 8 and a loudspeaker 9. The auto navigator itselfcontains suitable sensors for determining the instantaneous position(position finding), a mass storage unit for road maps, and a computer,which, from the instantaneous position and an entered destination,computes a route recommendation and describes this to the user with theaid of display device 7. This can be effected in known auto navigators,for example, by displaying a map with a highlighted route or in the formof instructions on how to proceed at intersections and turn-offs--i.e.,through arrow symbols for straight ahead, left, right, etc. Theinstructions can be supported verbally by loudspeaker 9. Apart fromthat, auto navigators of this type have been described in diverse ways,so there is no need for a detailed clarification in connection with thepresent invention.

In the device shown in FIG. 2, the high-frequency signals are suppliedby antenna 2 to a receiving part 12, from where the low-frequencysignals are fed to an RDS decoder 13. The TMC signal is extracted fromthe decoded RDS signal and supplied to a TMC decoder 14. Reserved in amemory 15 for each newly received traffic message is a storage location,which receives the message element with the following information:

    ______________________________________    Data:        Explanation:    ______________________________________    LOC1         received location code 1    LOC2         corresponding to the transmitted                 measurements of determined location code 2    Event code   event code    Diversion    yes/no information, whether detour                 information was transmitted via TMC    Event dir    indication, whether event is                 unidirectional or bidirectional    Time indication                 in hours and minutes    CSM/MSM      indication, whether a TMC single-                 sequential or multi-sequential message is                 at hand /2/    freeformat   free format, which contains all message                 contents of a multi-sequential message,                 2nd through 5th sequence    Start time   indicates from what instant on the event                 is valid    Stop time    indicates from what instant on the event                 is invalid    Database number                 TMC database number expanded by the                 country code    ______________________________________

This information is decoded with the help of a location list 16 and anevent list 17 to form an output. The following information is included,for example, in location list 16, loc. standing for location:

    ______________________________________    Data:      Explanation:       Example:    ______________________________________    Loc. Code  is the transmitted numerical                                  1, 2, . . .               code               2000, . . .    Loc. Type  describes the type of location                                  point, area,                                  street                                  segment    offset+    reference to the loc. code                                  previous               of the preceding point or                                  highway               segment along a street                                  exit/entrance    offset-    reference to the loc. code                                  next               of the following point or                                  highway               segment along a street                                  exit/entrance    RefL       when point loc.: reference               to the loc. code of the               corresponding street segment    RefA       when point loc.: reference to               the loc. code of the               corresponding area    Country    country code in accordance                                  defined for               with /1/           which country                                  of Europe the                                  loc. code                                  applies    DB code    data base no. /1/  defined for                                  the                                  corresponding                                  country, the                                  no. of the                                  loc. table    ______________________________________

Also included in location list 16 is data for converting the decodedtraffic message into a written or spoken text. This is likewise includedin a list of the following type stored at 16:

    ______________________________________    Data:        Description:   Example:    ______________________________________    Road description                 Type of street A1 = highway1,                                A5 (M1)    Road name    specific name  Cologne Ring;    Loc sub type Additional description                                e.g. at point:                 for loc. type  highway junction;                                triangle, . . .    Name1        name of the location                                e.g., Hildesheim                                Drispenstedt    Name2        2nd name of the                                only at street                 location       segment (end                                point)    Coordinates  geographic coordinates                                degrees, minutes,    (geogr. length                 for map display                                seconds    and width)    ______________________________________

Traffic messages, which need to be presented to the user, can be outputby means of a voice synthesizer 18, an amplifier 19, and loudspeaker 3.Moreover, the TMC system is linked to an operating control unit 4 and toa display 20. By way of operating control unit 4, the user can inputselection criteria for traffic messages, so that only those trafficmessages which pertain to his or her route, for example, are output tohim or her. Display device 20 can be used to show operational controlprocesses or also to present traffic messages in text form.

Auto navigator 6 having a display device 7 and an operating control unit8 is linked via data bus 5 to the TMC system. Other components connectedto auto navigator 6 are sensors 21, e.g., a GPS receiver, a memorydevice 22 for a road map, which besides the necessary information forauto navigator 6 also contains information for the TMC system, and amain immediate access memory 25 for buffering traffic messages and otherresults of the route planning.

FIG. 3 illustrates the essential steps in an initialization of the TMCsystem and the auto navigator, to the extent that the data exchangebetween both systems is affected. Following a start at 31, the autonavigator queries at 32 whether data bus 5 and TMC system 14 areconnected at auto navigator 6 (FIG. 2). If this is not the case, theinitialization is interrupted, and the program is ended at 33. The autonavigator can then, in fact, fulfill its remaining tasks, but withoutthe support of the TMC system.

If the data bus and the TMC system are connected, then initializationdata are transmitted at 34 from the TMC system to auto navigator NAV, inparticular the time of day T, the number NR or several numbers from thelocation lists stored in the TMC system and from a status message. Thelatter describes the status of the TMC system, e.g., whether trafficmessages are stored or not.

It is checked in program part 35 whether the numbers NR transmitted tothe auto navigator from the location lists and TMC location codescorrespond to the digital road map MAP of the auto navigator. If this isnot the case, then no interaction is possible between the auto navigatorand the TMC system, and the initialization is ended at 33. However, ifsuitable location codes are present on the digital road map of the autonavigator, it is checked at 36 whether the user has input a traveldestination Z. If this is the case, the transmission of the existingtraffic messages to the auto navigator is started at 37. After that, theinitialization is ended at 38.

FIG. 4 shows the sequence for transmitting data via data bus 5 (FIG. 1)when a new traffic message is received. The program is started at 41 andruns through a loop at 42 until a traffic message is received. It issubsequently checked in the TMC system at 43 whether the traffic messageis new (TMN) or whether it is a repetition of a traffic message alreadyreceived earlier. If the traffic message is not new, its time stamp,which is stored together with the traffic message in memory 15 (FIG. 2),is updated (ACT TS) at 44, and the program is ended at 45.

However, if the traffic message at 43 is new, it is stored at 46 inmemory 15 (FIG. 2). After that, it is checked at 47 whether theselection criterion valid at any one time is fulfilled (SEL+). If thisis not the case, then the program is ended at 45 without additionalmeasures. However, if the selection criterion is fulfilled, then thetraffic message is transmitted to the auto navigator in program part 48.After that, the traffic message is flagged (49) as having beenautomatically output, and the program is ended at 45.

The auto navigator is able to process the traffic messages transmittedin accordance with 48 and, in particular, to consider them in thecalculation of route recommendations. However, to only have to processthose traffic messages which are relevant for the calculation of routerecommendations on the basis of the instantaneous position and theentered destination, the auto navigator transmits new positions and newselection criteria to the TMC system. The new position can be thereby betransmitted in each case in predefined time periods or in accordancewith predefined distances.

Reporting the new position or the new selection criterion to the TMCsystem would mean per se that merely the TMC messages being received aretransmitted to the auto navigator as messages that have been selectedaccordingly. However, traffic messages that had not been relevant beforethe selection criterion was changed or at the previous position, cangain significance in the calculation of the route recommendation.Therefore, a new selection is made for every new position and for everynew selection criterion and, if applicable, the stored traffic messagesare transmitted to the auto navigator in accordance with FIG. 5. After astart at 51, a counter n is set to 0 at 52.

A branching follows at 53 depending on whether the traffic message TM(n)satisfies the new selection criterion. If this is the case, the trafficmessage is flagged accordingly at 54. After that, a branching 55 followsin dependence upon whether the traffic message had already been outputonce or transmitted once to the auto navigator. If this is not the case,the transmission to the auto navigator follows at 56. Given a trafficmessage that had already been output earlier and a selection criterionthat has not been satisfied at 53, counter n is subsequently incrementedat 57. It is then checked at 58 whether counter n has reached the entirenumber N of traffic messages. For as long as this is not the case, theprogram is repeated, beginning with branch 53. If counter has reachedthe entire number N of traffic messages, the program is ended at 59.

FIG. 6 illustrates an example of a dynamic route recommendation beingderived by the auto navigator. At 61, the auto navigator NAV receivesthe traffic message TM from the TMC system, whereupon the eventcontained in the traffic message is decoded at 62 (DEC EVENT). It isthen checked at 63 whether the event is relevant to the calculation of aroute (EVENT REL?). Thus, for example, weather messages, as a rule, donot give cause to deviate from an initially recommended route, whiletraffic jams often do. If the event is relevant, the locations LOC, theroute length EXT, and the street type RT are decoded at 64. While thecoding of the traffic messages TM is essentially supported by the codingof selected locations, for example street intersections, highway exitsand entrances, highway junctions and small towns, information isavailable to the auto navigator in the form of road maps. For thatreason, various information is also converted at 64. Thus, for example,measurements transmitted along with a traffic message through indicationof the locations in question are converted into a kilometer value.

Taking the traffic message into consideration, a traffic resistancevalue R is calculated at 65 for the initially designated route. At 66,the traffic resistance value RA of alternative routes is calculated. Ifthe resistance value RA of the most favorable alternative route issmaller at 67 than the resistance value R of the initially designatedroute, the most favorable alternative route is recommended at 68. Thus,for example, a timely representation on display device 7 (FIG. 2)prompts the user to turn off from the initially designated route.Moreover, a voice alert makes the user aware of a route change at 69,and a later outputting of traffic messages relating to the initiallydesignated route being suppressed in some instances.

However, if none of the traffic resistance values RA of the alternativeroute are smaller than the traffic resistance value R of the initiallydesignated route, then no change in the route recommendation is made,but rather the program is repeated, starting at 61.

What is claimed is:
 1. A device for editing and outputting informationfor a driver of a motor vehicle comprising:a receiver for receiving atleast one digitally coded traffic message; an auto navigator fordetermining an instantaneous position of the motor vehicle and at leastone route recommendation; a data transmission device coupling thereceiver and the auto navigator; and at least one output device; whereinthe auto navigator determines at least one criterion for selecting atleast one digitally coded traffic message to be transmitted to the autonavigator from the instantaneous position and an entered destination andtransmits the at least one criterion to the receiver wherein the atleast one criterion for selecting at least one digitally coded trafficmessage to be output is transmitted by the auto navigator to thereceiver, and wherein the at least one criterion is used to select atleast one digitally coded traffic message relating to a first routerecommendation determined by the auto navigator when the auto navigatorcan determine no other route recommendation.
 2. A device for editing andoutputting information for a driver of a motor vehicle comprising:areceiver for receiving at least one digitally coded traffic message; anauto navigator for determining an instantaneous position of the motorvehicle and at least one route recommendation; a data transmissiondevice coupling the receiver and the auto navigator; and at least oneoutput device; wherein the auto navigator determines a first criterionfor selecting at least one digitally coded traffic message to betransmitted to the auto navigator from the instantaneous position and anentered destination and transmits the first criterion to the receiver,and wherein the at least one traffic message to be sent to the at leastone output device is selected using a second criterion that is enteredindependently of the auto navigator and the first criterion.
 3. A devicefor editing and outputting information for a driver of a motor vehiclecomprising:a receiver for receiving at least one digitally coded trafficmessage; an auto navigator for determining an instantaneous position ofthe motor vehicle and at least one route recommendation; and a datatransmission device coupling the receiver and the auto navigator;wherein depending on a selection by the driver the at least onedigitally coded traffic message is selected using at least one of afirst criterion that is entered by the driver independently of the autonavigator and a second criterion that is determined by the autonavigator.